ASTM C1231/C1231M-14

Standard Practice for Use of Unbonded Caps in Determination of Compressive Strength of Hardened Concrete Cylinders

SIGNIFICANCE AND USE
4.1 This practice provides for using an unbonded capping system in testing hardened concrete cylinders made in accordance with Practices C31/C31M or C192/C192M in lieu of the capping systems described in Practice C617.  
4.2 The elastomeric pads deform in initial loading to conform to the contour of the ends of the cylinder and are restrained from excessive lateral spreading by plates and metal rings to provide a uniform distribution of load from the bearing blocks of the testing machine to the ends of the concrete or mortar cylinders.
SCOPE
1.1 This practice covers requirements for a capping system using unbonded caps for testing concrete cylinders molded in accordance with Practice C31/C31M or C192/C192M. Unbonded neoprene caps of a defined hardness are permitted to be used for testing for a specified maximum number of reuses without qualification testing up to a certain concrete compressive strength level. Above that strength, level neoprene caps will require qualification testing. Qualification testing is required for all elastomeric materials other than neoprene regardless of the concrete strength.  
1.2 Unbonded caps are not to be used for acceptance testing of concrete with compressive strength below 10 MPa [1500 psi ] or above 80 MPa [12 000 psi].  
1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. (Warning—Concrete cylinders tested with unbonded caps rupture more violently than comparable cylinders tested with bonded caps. The safety precautions given in the Manual of Aggregate and Concrete Testing are recommended.2)

General Information

• Status: Historical
• Publication Date: 30-Jun-2014
• ICS: 91.100.30 - Concrete and concrete products
• Technical Committee: C09 - Concrete and Concrete Aggregates
• Drafting Committee: C09.61 - Testing for Strength

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: C1231/C1231M − 14
StandardPractice for
Use of Unbonded Caps in Determination of Compressive
1
Strength of Hardened Concrete Cylinders
This standard is issued under the fixed designation C1231/C1231M; the number immediately following the designation indicates the
year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last
reapproval. A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope* 2. Referenced Documents
3
1.1 This practice covers requirements for a capping system 2.1 ASTM Standards:
using unbonded caps for testing concrete cylinders molded in C31/C31MPractice for Making and Curing Concrete Test
accordance with Practice C31/C31M or C192/C192M. Un- Specimens in the Field
bonded neoprene caps of a defined hardness are permitted to C39/C39MTest Method for Compressive Strength of Cylin-
be used for testing for a specified maximum number of reuses drical Concrete Specimens
without qualification testing up to a certain concrete compres- C192/C192MPractice for Making and Curing ConcreteTest
sive strength level. Above that strength, level neoprene caps Specimens in the Laboratory
will require qualification testing. Qualification testing is re- C617Practice for Capping Cylindrical Concrete Specimens
quired for all elastomeric materials other than neoprene D2000Classification System for Rubber Products in Auto-
regardless of the concrete strength. motive Applications
1.2 Unbondedcapsarenottobeusedforacceptancetesting
3. Terminology
ofconcretewithcompressivestrengthbelow10MPa[1500psi
3.1 Definitions of Terms Specific to This Standard:
] or above 80 MPa [12 000 psi].
3.1.1 pad, n—an unbonded elastomeric pad.
1.3 The values stated in either SI units or inch-pound units
3.1.2 unbonded cap, n—a metal retainer and an elastomeric
are to be regarded separately as standard. The values stated in
pad.
each system may not be exact equivalents; therefore, each
system shall be used independently of the other. Combining 4. Significance and Use
values from the two systems may result in non-conformance
4.1 This practice provides for using an unbonded capping
with the standard.
system in testing hardened concrete cylinders made in accor-
1.4 This standard does not purport to address all of the
dance with Practices C31/C31M or C192/C192M in lieu of the
safety concerns, if any, associated with its use. It is the
capping systems described in Practice C617.
responsibility of the user of this standard to establish appro-
4.2 The elastomeric pads deform in initial loading to con-
priate safety and health practices and determine the applica-
form to the contour of the ends of the cylinder and are
bility of regulatory limitations prior to use. (Warning—
restrained from excessive lateral spreading by plates and metal
Concrete cylinders tested with unbonded caps rupture more
ringstoprovideauniformdistributionofloadfromthebearing
violently than comparable cylinders tested with bonded caps.
blocks of the testing machine to the ends of the concrete or
The safety precautions given in the Manual of Aggregate and
mortar cylinders.
2
Concrete Testing are recommended. )
5. Materials and Apparatus
5.1 Materials and equipment necessary to produce ends of
1
This practice is under the jurisdiction of ASTM Committee C09 on Concrete
the reference cylinders that conform to planeness requirements
andConcreteAggregatesandisthedirectresponsibilityofSubcommitteeC09.61on
of Test Method C39/C39M and the requirements of Practice
Testing for Strength.
CurrenteditionapprovedJuly1,2014.PublishedJuly2014.Originallyapproved
3
in 1993. Last previous edition approved in 2013 as C1231/C1231M – 13. DOI: For referenced ASTM standards, visit the ASTM website, www.astm.org, or
10.1520/C1231_C1231M-14. contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
2
Section on Safety Precautions, Manual of Aggregate and Concrete Testing, Standards volume information, refer to the standard’s Document Summary page on
Annual Book of ASTM Standards, Vol 04.02. the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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C1231/C1231M − 14
C617. This may include grinding equipment or capping mate- grooves, protrusions, or indentations greater than 0.25 mm
2 2
rials and equipment to produce neat cement paste, high [0.010 in.] deep or greater than 32 mm [0.05 in. ] in surface
strength gypsum plaster, or sulfur mortar caps. area.
5.2 Elastomeric Pads:
NOTE 1—Retainers made from steel and some aluminum alloys have
1 1
been found acceptable.
5.2.1 Pads shall be 13 62mm[ ⁄2 6 ⁄16 in.] thick and
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: C1231/C1231M − 13 C1231/C1231M − 14
Standard Practice for
Use of Unbonded Caps in Determination of Compressive
1
Strength of Hardened Concrete Cylinders
This standard is issued under the fixed designation C1231/C1231M; the number immediately following the designation indicates the
year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last
reapproval. A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope*
1.1 This practice covers requirements for a capping system using unbonded caps for testing concrete cylinders molded in
accordance with Practice C31/C31M or C192/C192M. Unbonded neoprene caps of a defined hardness are permitted to be used
for testing for a specified maximum number of reuses without qualification testing up to a certain concrete compressive strength
level. Above that strength, level neoprene caps will require qualification testing. Qualification testing is required for all elastomeric
materials other than neoprene regardless of the concrete strength.
1.2 Unbonded caps are not to be used for acceptance testing of concrete with compressive strength below 1500 psi [10 MPa]
or above 12 000 psi [80 MPa].10 MPa [1500 psi ] or above 80 MPa [12 000 psi].
1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each
system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the
two systems may result in non-conformance with the standard.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use. (Warning—Concrete cylinders tested with unbonded caps rupture more violently than comparable
cylinders tested with bonded caps. The safety precautions given in the Manual of Aggregate and Concrete Testing are
2
recommended. Warning—Concrete cylinders tested with unbonded caps rupture more violently than comparable cylinders tested
with bonded caps. The safety precautions given in the Manual of Aggregate and Concrete Testing are recommended.)
2. Referenced Documents
3
2.1 ASTM Standards:
C31/C31M Practice for Making and Curing Concrete Test Specimens in the Field
C39/C39M Test Method for Compressive Strength of Cylindrical Concrete Specimens
C192/C192M Practice for Making and Curing Concrete Test Specimens in the Laboratory
C617 Practice for Capping Cylindrical Concrete Specimens
D2000 Classification System for Rubber Products in Automotive Applications
3. Terminology
3.1 Definitions of Terms Specific to This Standard:
3.1.1 pad, n—an unbonded elastomeric pad.
3.1.2 unbonded cap, n—a metal retainer and an elastomeric pad.
4. Significance and Use
4.1 This practice provides for using an unbonded capping system in testing hardened concrete cylinders made in accordance
with Practices C31/C31M or C192/C192M in lieu of the capping systems described in Practice C617.
1
This practice is under the jurisdiction of ASTM Committee C09 on Concrete and Concrete Aggregates and is the direct responsibility of Subcommittee C09.61 on Testing
for Strength.
Current edition approved Dec. 15, 2013July 1, 2014. Published January 2014July 2014. Originally approved in 1993. Last previous edition approved in 20122013 as
C1231/C1231M–12. DOI: 10.1520/C1231_C1231M-13. – 13. DOI: 10.1520/C1231_C1231M-14.
2
Section on Safety Precautions, Manual of Aggregate and Concrete Testing, Annual Book of ASTM Standards, Vol.Vol 04.02.
3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
C1231/C1231M − 14
4.2 The elastomeric pads deform in initial loading to conform to the contour of the ends of the cylinder and are restrained from
excessive lateral spreading by plates and metal rings to provide a uniform distribution of load from the bearing blocks of the testing
machine to the ends of the concrete or mortar cyli
...